A myriad of Central Nervous System (CNS) anomalies have been identified in abstinent alcoholic patients. These deficits have been observed with the use of various techniques such as computerized axial tomography (CAT), Magnetic Resonance Imaging (MRI), Evoked Brain Potentials (EBP), Electroencephalography (EEG) and Neuropsychological tests (NP). Until recently, the aforementioned CNS deficits observed in alcoholics have been interpreted to reflect the deleterions effects of alcohol abuse. Neurophysiological studies now indicate that some of the deficits noted in abstinent alcoholics are also present in young sons of alcoholics not exposed to alcohol. Furthermore, recent evidence indicates that alcoholism is not a homogeneous disease. The presence or absence of a family history of alcoholism alone does not account for the clinically disparate subgroups of alcoholics. Thus there is evidence for both clinical and genetic heterogeneity in alcoholism. We propose to conduct several neurophysiological (EBP and EEG) studies in different homogeneous subgroups of abstinent alcoholics classified according to specific clinical as well as genetic (family history) variables. Moreover, the clinical subgroups (Type 1 -Type 2) will also be assessed for the presence or absence of specific heritable personality traits. The proposed studies should provide significant data on etiological factors involved in alcoholism.